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  <div class="headertitle"><div class="title">option_set.cpp</div></div>
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<a href="option__set_8cpp.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a id="l00001" name="l00001"></a><span class="lineno">    1</span><span class="comment">/* Flow</span></div>
<div class="line"><a id="l00002" name="l00002"></a><span class="lineno">    2</span><span class="comment"> * Copyright 2023 Akamai Technologies, Inc.</span></div>
<div class="line"><a id="l00003" name="l00003"></a><span class="lineno">    3</span><span class="comment"> *</span></div>
<div class="line"><a id="l00004" name="l00004"></a><span class="lineno">    4</span><span class="comment"> * Licensed under the Apache License, Version 2.0 (the</span></div>
<div class="line"><a id="l00005" name="l00005"></a><span class="lineno">    5</span><span class="comment"> * &quot;License&quot;); you may not use this file except in</span></div>
<div class="line"><a id="l00006" name="l00006"></a><span class="lineno">    6</span><span class="comment"> * compliance with the License.  You may obtain a copy</span></div>
<div class="line"><a id="l00007" name="l00007"></a><span class="lineno">    7</span><span class="comment"> * of the License at</span></div>
<div class="line"><a id="l00008" name="l00008"></a><span class="lineno">    8</span><span class="comment"> *</span></div>
<div class="line"><a id="l00009" name="l00009"></a><span class="lineno">    9</span><span class="comment"> *   https://www.apache.org/licenses/LICENSE-2.0</span></div>
<div class="line"><a id="l00010" name="l00010"></a><span class="lineno">   10</span><span class="comment"> *</span></div>
<div class="line"><a id="l00011" name="l00011"></a><span class="lineno">   11</span><span class="comment"> * Unless required by applicable law or agreed to in</span></div>
<div class="line"><a id="l00012" name="l00012"></a><span class="lineno">   12</span><span class="comment"> * writing, software distributed under the License is</span></div>
<div class="line"><a id="l00013" name="l00013"></a><span class="lineno">   13</span><span class="comment"> * distributed on an &quot;AS IS&quot; BASIS, WITHOUT WARRANTIES OR</span></div>
<div class="line"><a id="l00014" name="l00014"></a><span class="lineno">   14</span><span class="comment"> * CONDITIONS OF ANY KIND, either express or implied.</span></div>
<div class="line"><a id="l00015" name="l00015"></a><span class="lineno">   15</span><span class="comment"> * See the License for the specific language governing</span></div>
<div class="line"><a id="l00016" name="l00016"></a><span class="lineno">   16</span><span class="comment"> * permissions and limitations under the License. */</span></div>
<div class="line"><a id="l00017" name="l00017"></a><span class="lineno">   17</span><span class="comment"></span> </div>
<div class="line"><a id="l00018" name="l00018"></a><span class="lineno">   18</span><span class="comment">/// @file</span></div>
<div class="line"><a id="l00019" name="l00019"></a><span class="lineno">   19</span><span class="comment"></span><span class="preprocessor">#include &quot;<a class="code" href="option__set_8hpp.html">flow/cfg/option_set.hpp</a>&quot;</span></div>
<div class="line"><a id="l00020" name="l00020"></a><span class="lineno">   20</span><span class="preprocessor">#include &lt;boost/algorithm/string.hpp&gt;</span></div>
<div class="line"><a id="l00021" name="l00021"></a><span class="lineno">   21</span><span class="preprocessor">#include &lt;boost/algorithm/string/trim_all.hpp&gt;</span></div>
<div class="line"><a id="l00022" name="l00022"></a><span class="lineno">   22</span> </div>
<div class="line"><a id="l00023" name="l00023"></a><span class="lineno">   23</span><span class="keyword">namespace </span><a class="code hl_namespace" href="namespaceflow_1_1cfg.html">flow::cfg</a></div>
<div class="line"><a id="l00024" name="l00024"></a><span class="lineno">   24</span>{</div>
<div class="line"><a id="l00025" name="l00025"></a><span class="lineno">   25</span><span class="comment">// Static/etc. initializers.</span></div>
<div class="line"><a id="l00026" name="l00026"></a><span class="lineno">   26</span><span class="comment"></span> </div>
<div class="line"><a id="l00027" name="l00027"></a><span class="lineno">   27</span><span class="comment">/// @cond</span></div>
<div class="line"><a id="l00028" name="l00028"></a><span class="lineno">   28</span><span class="comment"></span><span class="comment">// -^- Doxygen, please ignore the following.  It gets confused thinking this is a macro (@todo fix whenever).</span></div>
<div class="line"><a id="l00029" name="l00029"></a><span class="lineno">   29</span> </div>
<div class="line"><a id="l00030" name="l00030"></a><span class="lineno">   30</span><span class="comment">// Just see the guy that uses it.  I wish it could be a local `constexpr`.  @todo Maybe it can?</span></div>
<div class="line"><a id="l00031" name="l00031"></a><span class="lineno">   31</span><span class="keyword">const</span> boost::regex <a class="code hl_variable" href="namespaceflow_1_1cfg.html#ac2f99fdb8f743e12d8f92553292dc8d6">VALUE_SET_MEMBER_ID_TO_OPT_NAME_KEYED_REGEX</a>(<span class="stringliteral">&quot;(.+)\\[[^]]+\\](.+)&quot;</span>);</div>
<div class="line"><a id="l00032" name="l00032"></a><span class="lineno">   32</span> </div>
<div class="line"><a id="l00033" name="l00033"></a><span class="lineno">   33</span><span class="comment">// -v- Doxygen, please stop ignoring.</span><span class="comment"></span></div>
<div class="line"><a id="l00034" name="l00034"></a><span class="lineno">   34</span><span class="comment">/// @endcond</span></div>
<div class="line"><a id="l00035" name="l00035"></a><span class="lineno">   35</span><span class="comment"></span> </div>
<div class="line"><a id="l00036" name="l00036"></a><span class="lineno">   36</span><span class="comment">// Implementations.</span></div>
<div class="line"><a id="l00037" name="l00037"></a><span class="lineno">   37</span> </div>
<div class="line"><a id="l00038" name="l00038"></a><span class="lineno"><a class="line" href="namespaceflow_1_1cfg.html#a696eee859b6e3f0fc0b6473a1d2836b0">   38</a></span>std::string <a class="code hl_function" href="namespaceflow_1_1cfg.html#a696eee859b6e3f0fc0b6473a1d2836b0">value_set_member_id_to_opt_name</a>(<a class="code hl_typedef" href="namespaceflow_1_1util.html#ae4dc52186797094b3040379ff19124c9">util::String_view</a> member_id)</div>
<div class="line"><a id="l00039" name="l00039"></a><span class="lineno">   39</span>{</div>
<div class="line"><a id="l00040" name="l00040"></a><span class="lineno">   40</span>  <span class="keyword">using </span><a class="code hl_typedef" href="namespaceflow_1_1util.html#ae4dc52186797094b3040379ff19124c9">util::String_view</a>;</div>
<div class="line"><a id="l00041" name="l00041"></a><span class="lineno">   41</span>  <span class="keyword">using </span>std::string;</div>
<div class="line"><a id="l00042" name="l00042"></a><span class="lineno">   42</span>  <span class="keyword">using </span>boost::algorithm::replace_all;</div>
<div class="line"><a id="l00043" name="l00043"></a><span class="lineno">   43</span>  <span class="keyword">using </span>boost::algorithm::starts_with;</div>
<div class="line"><a id="l00044" name="l00044"></a><span class="lineno">   44</span>  <span class="keyword">using </span>boost::algorithm::is_any_of;</div>
<div class="line"><a id="l00045" name="l00045"></a><span class="lineno">   45</span>  <span class="keyword">using </span>boost::algorithm::trim_fill_if;</div>
<div class="line"><a id="l00046" name="l00046"></a><span class="lineno">   46</span>  <span class="keyword">using </span>std::replace;</div>
<div class="line"><a id="l00047" name="l00047"></a><span class="lineno">   47</span> </div>
<div class="line"><a id="l00048" name="l00048"></a><span class="lineno">   48</span>  <span class="comment">/* E.g. m_cool_object.m_cool_sub_object-&gt;m_badass_sub_guy.m_cool_option_name</span></div>
<div class="line"><a id="l00049" name="l00049"></a><span class="lineno">   49</span><span class="comment">   *   =&gt; cool-object.cool-sub-object.badass-sub-guy.cool-option-name.</span></div>
<div class="line"><a id="l00050" name="l00050"></a><span class="lineno">   50</span><span class="comment">   * Note, by the way, that in config files as parsed by boost.program_options, one can declare a section like:</span></div>
<div class="line"><a id="l00051" name="l00051"></a><span class="lineno">   51</span><span class="comment">   *   [cool-object]</span></div>
<div class="line"><a id="l00052" name="l00052"></a><span class="lineno">   52</span><span class="comment">   *   cool-option-1</span></div>
<div class="line"><a id="l00053" name="l00053"></a><span class="lineno">   53</span><span class="comment">   *   badass-option-2</span></div>
<div class="line"><a id="l00054" name="l00054"></a><span class="lineno">   54</span><span class="comment">   * which will parse the 2 as cool-object.cool-option-1 and cool-object.badass-option-2.  Synergy!</span></div>
<div class="line"><a id="l00055" name="l00055"></a><span class="lineno">   55</span><span class="comment">   *</span></div>
<div class="line"><a id="l00056" name="l00056"></a><span class="lineno">   56</span><span class="comment">   * Also #blah does not remove (at least some) white-space that&#39;s part of the original source code `blah`, so we have</span></div>
<div class="line"><a id="l00057" name="l00057"></a><span class="lineno">   57</span><span class="comment">   * to eliminate all those first.  For reference here&#39;s what gcc docs say about the &quot;stringizing&quot; algorithm.  (I have</span></div>
<div class="line"><a id="l00058" name="l00058"></a><span class="lineno">   58</span><span class="comment">   * not verified how this relates to C/C++ standards.)</span></div>
<div class="line"><a id="l00059" name="l00059"></a><span class="lineno">   59</span><span class="comment">   *   &quot;All leading and trailing whitespace in text being stringized is ignored.&quot;</span></div>
<div class="line"><a id="l00060" name="l00060"></a><span class="lineno">   60</span><span class="comment">   *   - Nevertheless we&#39;d still nuke it.</span></div>
<div class="line"><a id="l00061" name="l00061"></a><span class="lineno">   61</span><span class="comment">   *   &quot;Any sequence of whitespace in the middle of the text is converted to a single space in the stringized result.&quot;</span></div>
<div class="line"><a id="l00062" name="l00062"></a><span class="lineno">   62</span><span class="comment">   *   - Cool, but in any case we nuke all space-y chars.</span></div>
<div class="line"><a id="l00063" name="l00063"></a><span class="lineno">   63</span><span class="comment">   *   &quot;Comments are replaced by whitespace long before stringizing happens, so they never appear in stringized text.&quot;</span></div>
<div class="line"><a id="l00064" name="l00064"></a><span class="lineno">   64</span><span class="comment">   *   - That&#39;s good.</span></div>
<div class="line"><a id="l00065" name="l00065"></a><span class="lineno">   65</span><span class="comment">   *</span></div>
<div class="line"><a id="l00066" name="l00066"></a><span class="lineno">   66</span><span class="comment">   * Other activity involves auto-escaping string/char literals inside `blah`, but that doesn&#39;t apply to us. */</span></div>
<div class="line"><a id="l00067" name="l00067"></a><span class="lineno">   67</span> </div>
<div class="line"><a id="l00068" name="l00068"></a><span class="lineno">   68</span>  <span class="keyword">constexpr</span> <a class="code hl_typedef" href="namespaceflow_1_1util.html#ae4dc52186797094b3040379ff19124c9">String_view</a> M_PFX(<span class="stringliteral">&quot;m_&quot;</span>);</div>
<div class="line"><a id="l00069" name="l00069"></a><span class="lineno">   69</span>  <span class="keyword">constexpr</span> <a class="code hl_typedef" href="namespaceflow_1_1util.html#ae4dc52186797094b3040379ff19124c9">String_view</a> CONCAT_OK(<span class="stringliteral">&quot;.&quot;</span>); <span class="comment">// Dots remain (but if followed by m_, get rid of m_).</span></div>
<div class="line"><a id="l00070" name="l00070"></a><span class="lineno">   70</span>  <span class="keyword">constexpr</span> <a class="code hl_typedef" href="namespaceflow_1_1util.html#ae4dc52186797094b3040379ff19124c9">String_view</a> CONCAT_REPLACED(<span class="stringliteral">&quot;-&gt;&quot;</span>); <span class="comment">// -&gt; become dots (and again if m_ follows, get rid of it).</span></div>
<div class="line"><a id="l00071" name="l00071"></a><span class="lineno">   71</span>  <span class="keyword">constexpr</span> <span class="keywordtype">char</span> SEP_REPLACED = <span class="charliteral">&#39;_&#39;</span>; <span class="comment">// From this...</span></div>
<div class="line"><a id="l00072" name="l00072"></a><span class="lineno">   72</span>  <span class="keyword">constexpr</span> <span class="keywordtype">char</span> SEP_REPLACEMENT = <span class="charliteral">&#39;-&#39;</span>; <span class="comment">// ...to this.</span></div>
<div class="line"><a id="l00073" name="l00073"></a><span class="lineno">   73</span> </div>
<div class="line"><a id="l00074" name="l00074"></a><span class="lineno">   74</span>  <span class="keywordtype">string</span> opt_name(member_id);</div>
<div class="line"><a id="l00075" name="l00075"></a><span class="lineno">   75</span> </div>
<div class="line"><a id="l00076" name="l00076"></a><span class="lineno">   76</span>  <span class="comment">/* Nuke space-y chars.</span></div>
<div class="line"><a id="l00077" name="l00077"></a><span class="lineno">   77</span><span class="comment">   * Am paranoid about locales; and also didn&#39;t feel like using &lt;locale&gt; std::isspace(..., std::locale(&quot;C&quot;)). */</span></div>
<div class="line"><a id="l00078" name="l00078"></a><span class="lineno">   78</span>  trim_fill_if(opt_name, <span class="stringliteral">&quot;&quot;</span>, is_any_of(<span class="stringliteral">&quot; \f\n\r\t\v&quot;</span>));</div>
<div class="line"><a id="l00079" name="l00079"></a><span class="lineno">   79</span> </div>
<div class="line"><a id="l00080" name="l00080"></a><span class="lineno">   80</span>  <span class="comment">// Should now be a contiguous identifier-composed compound.</span></div>
<div class="line"><a id="l00081" name="l00081"></a><span class="lineno">   81</span> </div>
<div class="line"><a id="l00082" name="l00082"></a><span class="lineno">   82</span>  <span class="comment">// Eliminate leading M_PFX.</span></div>
<div class="line"><a id="l00083" name="l00083"></a><span class="lineno">   83</span>  <span class="keywordflow">if</span> (starts_with(opt_name, M_PFX))</div>
<div class="line"><a id="l00084" name="l00084"></a><span class="lineno">   84</span>  {</div>
<div class="line"><a id="l00085" name="l00085"></a><span class="lineno">   85</span>    opt_name.erase(0, M_PFX.size());</div>
<div class="line"><a id="l00086" name="l00086"></a><span class="lineno">   86</span>  }</div>
<div class="line"><a id="l00087" name="l00087"></a><span class="lineno">   87</span> </div>
<div class="line"><a id="l00088" name="l00088"></a><span class="lineno">   88</span>  <span class="comment">// Normalize object separators.</span></div>
<div class="line"><a id="l00089" name="l00089"></a><span class="lineno">   89</span>  replace_all(opt_name, CONCAT_REPLACED, CONCAT_OK);</div>
<div class="line"><a id="l00090" name="l00090"></a><span class="lineno">   90</span> </div>
<div class="line"><a id="l00091" name="l00091"></a><span class="lineno">   91</span>  <span class="comment">// Now any leading M_PFX gone; and object separators normalized to CONCAT_OK.  Can eliminate remaining M_PFX:</span></div>
<div class="line"><a id="l00092" name="l00092"></a><span class="lineno">   92</span>  replace_all(opt_name, <span class="keywordtype">string</span>(CONCAT_OK) + <span class="keywordtype">string</span>(M_PFX), CONCAT_OK);</div>
<div class="line"><a id="l00093" name="l00093"></a><span class="lineno">   93</span> </div>
<div class="line"><a id="l00094" name="l00094"></a><span class="lineno">   94</span>  <span class="comment">// Lastly transform the word-separators.</span></div>
<div class="line"><a id="l00095" name="l00095"></a><span class="lineno">   95</span>  replace(opt_name.begin(), opt_name.end(), SEP_REPLACED, SEP_REPLACEMENT);</div>
<div class="line"><a id="l00096" name="l00096"></a><span class="lineno">   96</span> </div>
<div class="line"><a id="l00097" name="l00097"></a><span class="lineno">   97</span>  <span class="keywordflow">return</span> opt_name;</div>
<div class="line"><a id="l00098" name="l00098"></a><span class="lineno">   98</span>} <span class="comment">// value_set_member_id_to_opt_name()</span></div>
<div class="line"><a id="l00099" name="l00099"></a><span class="lineno">   99</span> </div>
<div class="line"><a id="l00100" name="l00100"></a><span class="lineno">  100</span>} <span class="comment">// namespace flow::cfg</span></div>
<div class="line"><a id="l00101" name="l00101"></a><span class="lineno">  101</span> </div>
<div class="line"><a id="l00102" name="l00102"></a><span class="lineno">  102</span><span class="keyword">namespace </span><a class="code hl_namespace" href="namespaceboost_1_1filesystem.html">boost::filesystem</a></div>
<div class="line"><a id="l00103" name="l00103"></a><span class="lineno">  103</span>{</div>
<div class="line"><a id="l00104" name="l00104"></a><span class="lineno">  104</span><span class="comment">// Implementations.</span></div>
<div class="line"><a id="l00105" name="l00105"></a><span class="lineno">  105</span> </div>
<div class="line"><a id="l00106" name="l00106"></a><span class="lineno"><a class="line" href="namespaceboost_1_1filesystem.html#a5fa05fd030711d6d8c76139467b13256">  106</a></span><span class="keywordtype">void</span> <a class="code hl_function" href="namespaceboost_1_1filesystem.html#a5fa05fd030711d6d8c76139467b13256">validate</a>(boost::any&amp; target, <span class="keyword">const</span> std::vector&lt;std::string&gt;&amp; user_strings, path*, <span class="keywordtype">int</span>)</div>
<div class="line"><a id="l00107" name="l00107"></a><span class="lineno">  107</span>{</div>
<div class="line"><a id="l00108" name="l00108"></a><span class="lineno">  108</span>  <span class="comment">// Read our doc header for all background.  Hence only light comments below.</span></div>
<div class="line"><a id="l00109" name="l00109"></a><span class="lineno">  109</span> </div>
<div class="line"><a id="l00110" name="l00110"></a><span class="lineno">  110</span>  <span class="keyword">using </span><a class="code hl_class" href="classflow_1_1error_1_1Runtime__error.html">flow::error::Runtime_error</a>;</div>
<div class="line"><a id="l00111" name="l00111"></a><span class="lineno">  111</span>  <span class="keyword">using </span><a class="code hl_function" href="namespaceflow_1_1util.html#a685b86585da2fa5186f51854e7ae1561">flow::util::ostream_op_string</a>;</div>
<div class="line"><a id="l00112" name="l00112"></a><span class="lineno">  112</span>  <span class="keyword">namespace </span>opts = <a class="code hl_namespace" href="namespaceflow_1_1cfg_1_1opts.html">flow::cfg::opts</a>;</div>
<div class="line"><a id="l00113" name="l00113"></a><span class="lineno">  113</span>  <span class="keyword">using </span>boost::any;</div>
<div class="line"><a id="l00114" name="l00114"></a><span class="lineno">  114</span>  <span class="keyword">using </span>boost::lexical_cast;</div>
<div class="line"><a id="l00115" name="l00115"></a><span class="lineno">  115</span>  <span class="keyword">using </span>boost::bad_lexical_cast;</div>
<div class="line"><a id="l00116" name="l00116"></a><span class="lineno">  116</span>  <span class="keyword">using </span>std::string;</div>
<div class="line"><a id="l00117" name="l00117"></a><span class="lineno">  117</span> </div>
<div class="line"><a id="l00118" name="l00118"></a><span class="lineno">  118</span>  <span class="comment">// Note this is auto-trimmed of spaces on left and right.</span></div>
<div class="line"><a id="l00119" name="l00119"></a><span class="lineno">  119</span>  <span class="keyword">const</span> <span class="keywordtype">string</span>&amp; user_string = opts::validators::get_single_string(user_strings);</div>
<div class="line"><a id="l00120" name="l00120"></a><span class="lineno">  120</span>  <span class="comment">/* That threw if there&#39;s more than 1 string.  (I believe impossible in config file; but on command line they</span></div>
<div class="line"><a id="l00121" name="l00121"></a><span class="lineno">  121</span><span class="comment">   * could try, e.g., &quot;--log-path some-file.txt some-other-file.txt&quot; -- that would throw.) */</span></div>
<div class="line"><a id="l00122" name="l00122"></a><span class="lineno">  122</span> </div>
<div class="line"><a id="l00123" name="l00123"></a><span class="lineno">  123</span>  path result_path; <span class="comment">// Empty.</span></div>
<div class="line"><a id="l00124" name="l00124"></a><span class="lineno">  124</span>  <span class="keywordflow">if</span> (!user_string.empty())</div>
<div class="line"><a id="l00125" name="l00125"></a><span class="lineno">  125</span>  {</div>
<div class="line"><a id="l00126" name="l00126"></a><span class="lineno">  126</span>    <span class="comment">/* If not empty then just do what the default validate() would&#39;ve done: lexical_cast&lt;&gt; (i.e., istream&gt;&gt;) it.</span></div>
<div class="line"><a id="l00127" name="l00127"></a><span class="lineno">  127</span><span class="comment">     * Not actually sure what could still trip the exception other than &quot;&quot;; but re-throw it with a nice error, because</span></div>
<div class="line"><a id="l00128" name="l00128"></a><span class="lineno">  128</span><span class="comment">     * we can. */</span></div>
<div class="line"><a id="l00129" name="l00129"></a><span class="lineno">  129</span>    <span class="keywordflow">try</span></div>
<div class="line"><a id="l00130" name="l00130"></a><span class="lineno">  130</span>    {</div>
<div class="line"><a id="l00131" name="l00131"></a><span class="lineno">  131</span>      result_path = lexical_cast&lt;decltype(result_path)&gt;(user_string);</div>
<div class="line"><a id="l00132" name="l00132"></a><span class="lineno">  132</span>    }</div>
<div class="line"><a id="l00133" name="l00133"></a><span class="lineno">  133</span>    <span class="keywordflow">catch</span> (<span class="keyword">const</span> bad_lexical_cast&amp; exc)</div>
<div class="line"><a id="l00134" name="l00134"></a><span class="lineno">  134</span>    {</div>
<div class="line"><a id="l00135" name="l00135"></a><span class="lineno">  135</span>      <span class="keywordflow">throw</span> Runtime_error(<a class="code hl_function" href="namespaceflow_1_1util.html#a685b86585da2fa5186f51854e7ae1561">ostream_op_string</a></div>
<div class="line"><a id="l00136" name="l00136"></a><span class="lineno">  136</span>                            (<span class="stringliteral">&quot;Error converting [&quot;</span>, user_string,</div>
<div class="line"><a id="l00137" name="l00137"></a><span class="lineno">  137</span>                             <span class="stringliteral">&quot;] to boost::filesystem path.  Is there something strange in that string?&quot;</span>));</div>
<div class="line"><a id="l00138" name="l00138"></a><span class="lineno">  138</span>    }</div>
<div class="line"><a id="l00139" name="l00139"></a><span class="lineno">  139</span>  }</div>
<div class="line"><a id="l00140" name="l00140"></a><span class="lineno">  140</span>  <span class="comment">// else { Leave result_path at empty.  lexical_cast&lt;path&gt;(&quot;&quot;) would have yielded bad_lexical_cast, but we allow it. }</span></div>
<div class="line"><a id="l00141" name="l00141"></a><span class="lineno">  141</span> </div>
<div class="line"><a id="l00142" name="l00142"></a><span class="lineno">  142</span>  target = result_path; <span class="comment">// Load variable-type `target` with a `path`.</span></div>
<div class="line"><a id="l00143" name="l00143"></a><span class="lineno">  143</span>} <span class="comment">// validate(fs_path)</span></div>
<div class="line"><a id="l00144" name="l00144"></a><span class="lineno">  144</span> </div>
<div class="line"><a id="l00145" name="l00145"></a><span class="lineno">  145</span>} <span class="comment">// namespace boost::filesystem</span></div>
<div class="ttc" id="aclassflow_1_1error_1_1Runtime__error_html"><div class="ttname"><a href="classflow_1_1error_1_1Runtime__error.html">flow::error::Runtime_error</a></div><div class="ttdoc">An std::runtime_error (which is an std::exception) that stores an Error_code.</div><div class="ttdef"><b>Definition:</b> <a href="error_2error_8hpp_source.html#l00047">error.hpp:49</a></div></div>
<div class="ttc" id="anamespaceboost_1_1filesystem_html"><div class="ttname"><a href="namespaceboost_1_1filesystem.html">boost::filesystem</a></div><div class="ttdoc">We may add some ADL-based overloads into this namespace outside flow.</div><div class="ttdef"><b>Definition:</b> <a href="cfg__fwd_8hpp_source.html#l00266">cfg_fwd.hpp:267</a></div></div>
<div class="ttc" id="anamespaceboost_1_1filesystem_html_a5fa05fd030711d6d8c76139467b13256"><div class="ttname"><a href="namespaceboost_1_1filesystem.html#a5fa05fd030711d6d8c76139467b13256">boost::filesystem::validate</a></div><div class="ttdeci">void validate(boost::any &amp;target, const std::vector&lt; std::string &gt; &amp;user_values, path *, int)</div><div class="ttdoc">ADL-based overload of boost.program_options validate() to allow for empty boost::filesystem::path val...</div><div class="ttdef"><b>Definition:</b> <a href="option__set_8cpp_source.html#l00106">option_set.cpp:106</a></div></div>
<div class="ttc" id="anamespaceflow_1_1cfg_1_1opts_html"><div class="ttname"><a href="namespaceflow_1_1cfg_1_1opts.html">flow::cfg::opts</a></div><div class="ttdoc">Short-hand for namespace boost::program_options.</div></div>
<div class="ttc" id="anamespaceflow_1_1cfg_html"><div class="ttname"><a href="namespaceflow_1_1cfg.html">flow::cfg</a></div><div class="ttdoc">Flow module that facilitates configuring modules, such as applications and APIs, via statically and/o...</div><div class="ttdef"><b>Definition:</b> <a href="cfg__fwd_8hpp_source.html#l00111">cfg_fwd.hpp:112</a></div></div>
<div class="ttc" id="anamespaceflow_1_1cfg_html_a696eee859b6e3f0fc0b6473a1d2836b0"><div class="ttname"><a href="namespaceflow_1_1cfg.html#a696eee859b6e3f0fc0b6473a1d2836b0">flow::cfg::value_set_member_id_to_opt_name</a></div><div class="ttdeci">std::string value_set_member_id_to_opt_name(util::String_view member_id)</div><div class="ttdoc">Utility, used by FLOW_CFG_OPTION_SET_DECLARE_OPTION() internally but made available as a public API i...</div><div class="ttdef"><b>Definition:</b> <a href="option__set_8cpp_source.html#l00038">option_set.cpp:38</a></div></div>
<div class="ttc" id="anamespaceflow_1_1cfg_html_ac2f99fdb8f743e12d8f92553292dc8d6"><div class="ttname"><a href="namespaceflow_1_1cfg.html#ac2f99fdb8f743e12d8f92553292dc8d6">flow::cfg::VALUE_SET_MEMBER_ID_TO_OPT_NAME_KEYED_REGEX</a></div><div class="ttdeci">const boost::regex VALUE_SET_MEMBER_ID_TO_OPT_NAME_KEYED_REGEX</div><div class="ttdoc">An internal constant for value_set_member_id_to_opt_name_keyed().</div></div>
<div class="ttc" id="anamespaceflow_1_1util_html_a685b86585da2fa5186f51854e7ae1561"><div class="ttname"><a href="namespaceflow_1_1util.html#a685b86585da2fa5186f51854e7ae1561">flow::util::ostream_op_string</a></div><div class="ttdeci">std::string ostream_op_string(T const &amp;... ostream_args)</div><div class="ttdoc">Equivalent to ostream_op_to_string() but returns a new string by value instead of writing to the call...</div><div class="ttdef"><b>Definition:</b> <a href="util_2util_8hpp_source.html#l00381">util.hpp:381</a></div></div>
<div class="ttc" id="anamespaceflow_1_1util_html_ae4dc52186797094b3040379ff19124c9"><div class="ttname"><a href="namespaceflow_1_1util.html#ae4dc52186797094b3040379ff19124c9">flow::util::String_view</a></div><div class="ttdeci">Basic_string_view&lt; char &gt; String_view</div><div class="ttdoc">Commonly used char-based Basic_string_view. See its doc header.</div><div class="ttdef"><b>Definition:</b> <a href="string__view_8hpp_source.html#l00191">string_view.hpp:191</a></div></div>
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